1. Field of the Invention
The field of art to which the invention pertains includes the field of thermal barrier insulators, particularly, with respect to a insulative structure which can be utilized in a constantly varying gap while maintaining an aerodynamic mold line.
2. Description of the Prior Art
While numerous materials have been utilized to provide thermal barriers between the exterior and interior surface of space vehicles which are subjected to large temperature variations, none of these materials have been found to provide an effective thermal barrier insulator during re-entry where the exterior of the vehicle is subjected to high temperatures, while simultaneously maintaining an aerodynamic mold line. In addition, no insulative material has been found effective along a constantly varying gap due to relative movement between a pair of members of the space vehicle.
Typically such a thermal barrier insulator must provide the following features:
(1) Low thermal conductivity.
(2) High and low temperature capability (minus 470.degree.to 2,300.degree. F with present materials).
(3) Low load compressability.
(4) Ease of movement of the mating surfaces.
(5) Inhibition of plasma flow through the thermal barrier.